Enable configure of just sdbus++

Change-Id: I9910ef3c8d632ea4ed71dbf49c48c0cd798441f7
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/test/Makefile.am b/test/Makefile.am
index 15e8f72..e89fea1 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -1,3 +1,5 @@
+if WANT_LIBSDBUSPLUS
+
 AM_CPPFLAGS = -I$(top_srcdir)
 check_PROGRAMS =
 
@@ -25,3 +27,4 @@
 check_PROGRAMS += vtable_vtable
 vtable_vtable_SOURCES = vtable/vtable.cpp vtable/vtable_c.c
 
+endif